Agree. It's interesting and could be useful. But as with all 5-second demonstrations, one would have to play with it on a personal image to see the true benefits/drawbacks. In this test I can see that the right side of the building now has an unnatural warp to it (and could have been blurred as well - hard to tell on video). It's fairly subtle - easier to see by looking at the pathway in the grass on the right, which now has a soft S curve shape. So if we had a photo with detail throughout (as opposed to just running along the horizon line) - there would probably be some negative (unwanted) warping as well in the foreground along the "leveled" sides. Possibly in the background too - obviously we wouldn't see it in the sky in this example.